Differential pump.



L. H. JENSEN.

DIFFERENTIAL PUMP.

APPLICATION FILED OCT. 30, l9l6.

Patented June 11 1918..

INVENTOR.

% m LT .with the operating lever.

r r i LAWRENCE I-I. Jnnsnn', or sTJoHAnLEs', ILLINOIS.

DIFFERENTIAL PUMP.

Application filed October 30, 1916.

To all whom it may concern:

a citizenof the United States, and a resident of St. Charles, county of Kane, and State of Illinois, have invented certain new and useful Improvementsfinl Differential Pumps, of which the following isa specification. r

My invention relates to. manually operated piston pumps and more particularly to a pump for inflating vehicle tires and whichmay be readily mounted upon and temporarily secured to, the running board of motor vehicles and the like, and may be equally readily removed and disassembled and packed in a comparatively small space.

Among the divers objects ofmy invention is the provisionof a compression pump of the piston type, wherein the piston rod is adapted to be actuated or reciprocated through the medium of an operating lever that is suitably connected thereto by instrumentalities for increasing the leverageas pressure is developed in the pump cylinder. A further object of my invention is the pro vision of -means adapted to be interposed between and operatively connectthe piston rod and operating lever so that the initial movement of the piston will be relatively faster than the corresponding movement of the operatinglever,and the samemechanism is adapted to subsequently retard the speed of the movement of the piston so that it will travel at relatively the same speed Other objects of my invention will be obvious after an understandingof the same is had from the following description.

I prefer to accomplish the divers objects of my invention by substantially the means and in the manner hereinafter fully described and as more particularly pointed out in the claims, reference being had to the accompanying drawings forming a part of this specification, wherein, s

Figure 1 is a side elevation offmy improved pump attached to the running board of a motor vehicle, and showing the relative positions of the divers elements at the start of the pumping or compression operation.

Fig. 2 is a view similar to Fig. 1 after the operating lever or handle has traveled a considerable portion of its movement, and illustrating the relative change of position of the divers elements.

Fig. 3 is a fragmentary end view of my Specification of Letters Patent.

Patented June 11, 191a:

Serial No. 128,563.

improved pump, looking at the same from Bolt known that I, LAWRENCE H.- J ENsEN,

the right-hand or lever end of Fig. 1.

Fig. 4: is a fragmental perspective View of the manner of attaching the handle to the pump lever.

Referring to the drawings, wherein similar reference characters are employed to designate the respective elements through- 1 out the figures thereof, it will be observed a suitable yoke is provided that preferably comprises two correspondingly shaped, horizontally disposed side frames 5, 5, that consist of elongated bars having their rear ends connected to and carried by the parallel upright arms of a U- shaped bracket 6. adapted to rest upon the surface of the running board or other suitable support'7.

The opposite ends'of the side frames are connected by a suitable transverse bolt 8,

that also provides a support for an irregu larly shaped clamp 9 mounted thereon.

that is pivotally The pump cylinder 10 "has its rear end pivotally mountedbetween the arms of the.

U-shaped bracket 6 and is preferably carried by the same pins that secure the side frames 5 to said bracket arms. The usual reciprocablej piston and a. piston rod :12

upon which the same is mounted are provided in the cylinder.

. *Pivotally mounted at its lower end-upon the transverse bolt 8 is the actuating member for the piston rod which preferably comprises a second-class lever 13 formed of two corresponding irregularly shaped bars spaced apart and having their outer ends connected by a clamping screw or bolt 14L and the end edges of each bar are provided with a recess or socket 15. A suitable removable handle 16 is inserted between the end portions of these bars and said handle is provided with a recess or socket 17 in its end edge that is designed to seat on the shank of bolt 14 and is likewise provided with a transverse pin 18 that seats in the sockets 15 in the ends of the lever bars.

The means for operatively connecting the outer end of piston rod 12 to the actuating member preferably comprises a bell-crank 19, that is pivotally mounted at its apex on the lever 13 adjacent the fulcrum of the latter, and has one of its arms pivotally connected to the outer end of the piston rod 12. The bell-crank is preferably bifurcated or formed of two strips which separate slightly above their pivotal attachment to the piston rod so as to straddle the lever 13 at its apex and point of pivotal connection therewith. The straps at the opposite arm of the bellcrank are connected by a transverse pin 20 which extends through the irregular camslot 21 in a stationary plate 92 which is preferably secured between the side'frames 5 upon the bolt 8 heretofore referred to and an additional transverse pin 23 also eX- tended between and connecting said sideframes 5. The stationary plate 22 is preferably disposed centrally between the sideframes 5, and extends or is straddled by the bars of the lever 13.

The clamp 9 heretofore referred to is preferably pivoted to bolt 8 so that it may e folded parallel with the side-frame 5 for storage and shipment, as shown in dotted lines in Fig. 2 of the drawings, and adjacent the point of its attachment to the bolt 8 is provided with a lateral extension 24, which has a lug 25 adapted to engage one of the side-frames 5 when the clamp is in open or extended position, for the purpose of supplying additional means for holding the side-frames rigidly with respect to the running board 7 of the vehicle.

" The operation of my pump is as follows :Upon the commencement of the power stroke 1), the forcing of the pivotal connection at the apex of the bellcrank 19 toward the piston causes the pin 20 to travel downward in the irregular cam-slot 21. This develops a pivotal action of the bell-crank 19, which causes a relatively rapid movement of the piston rod secured to the opposite arm of the bell-crank. As the power stroke progresses the pin 20 travels forward in. the inwardly extending portion of the cam-slot 21, which, by modifying the extent of the rotary movement of the bell-crank, thereby modifies piston speed and. secures an increase of leverage power as the compression is developed in the pump cylinder.

What I claim is 1. A pump comprising a frame, a cylinder pivoted thereto, a piston and piston rod operable in said cylinder, a bell-crank one arm whereof is pivotally secured to said piston rod, a cam member operatively engaged by theother arm of said bellcrank, an actuating lever, and a pivotal connection between said bell-crank and said lever.

2. A pump comprising a cylinder, a piston and piston rod coacting therewith, a cam, a member one end whereof coacts with said cam and the other end is pivotally secured to said piston rod, and an actuating arm 'pivotally secured to said member intermediate the ends of the latter.

3. A pump comprising a cylinder,a piston and piston rod coacting therewith, a

lever fulcrumed adjacent said cam and pivotall secured intermediate its ends to said mem er intermediate the ends of the latter.

Signed at Chicago, county of Cook and State of Illinois, this 24th day of October, 1916. i

LAWRENCE H. JENSEN. Witnesses:

E. K. LUNDY, Jr., BENJ. T. Roonrrousn.

copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. G. 

